For years, food waste disposers have been suspended in various ways from tubular metal drain sleeve forms fastened in the drain opening of the sink. One common assembly for mounting a disposer on a sink includes a thin-walled stainless steel drain sleeve having an upper radially outwardly extending flange portion that contacts the sink surface adjacent the drain opening and a downwardly extending tubular portion. The lower end of the tubular portion protruding beneath the sink is provided with a radially outwardly opening groove receiving a snap ring to define a radially outwardly extending shoulder. Such shoulder carries a mounting ring having a plurality of tapped apertures. Bolts are screwed upwardly through the mounting ring apertures to contact an annular protection ring and press it upwardly against the bottom of the sink to draw the drain sleeve flange downwardly into fixed relation with the sink. These bolts may also couple the disposer to the drain sleeve. For this purpose, the upper end of the disposer hopper may have a radially outwardly extending flange with slots or openings therein for receipt of each bolt. The disposer flange is positioned proximate the drain sleeve so that each bolt extends through its respective slot or opening. Nuts are then secured to the lower projecting ends of the bolts and are tightened upwardly to secure the hopper flange against the mounting ring.
Other disposer mounting assemblies similar in arrangement to that described above have been used, and more recent assemblies have adopted quick connect and disconnect features to reduce transmitted vibrations. For examples of such assemblies, reference may be had to U.S. Pat. Nos. 3,768,742; 3,025,007; and 3,108,755.
The described disposer mount assemblies are believed to suffer from several structural and functional disadvantages. For example, the commonly used mounting bolts (customarily three in number) require tightening to secure the drain sleeve to the sink. Such bolt installation is awkward in the limited spatial confines beneath the sink and is also time consuming. In addition, the bolts and/or nuts may be unevenly tightened resulting in leaks at the drain opening, or in undesirable stress patterns being developed in the sink adjacent the drain opening which may lead to fracture or other damage to the sink. In addition, the snap rings commonly required in many prior art assemblies are difficult and time consuming to install, particularly by the lay person. A further disadvantage of many disposer mounting assemblies is that rotation of the disposer on its vertical axis is restricted after mounting. This makes the connection of the disposer to existing plumbing very difficult.